During the 01 and 02 years we have studied the effects of electro-acupuncture on two different types of experimental monkey preparations: one providing a behavioral assessment and the other a neurophysiological assessment. In these studies we have demonstrated that electro-acupuncture induces both behavioral and neurophysiological reactions indicative of analgesia. During the 03 year we intend to concentrate our efforts on chronic monkey preparations. In these experiments the analgesic effects of electro-acupuncture will be studied on evoked single thalamic neuronal activity and lever pressing threshold behavior, recorded concurrently in the same monkey. This experimental paradigm will permit a correlative measure of behavioral and concomitant neurophysiological responses to nociceptive stimulation from which a definitive assessment of electro-acupuncture's analgesic effectiveness may be derived.